Vacuum cleaner actuated by reconfiguration of the vacuum cleaner

ABSTRACT

A vacuum cleaner is reconfigurable between at least two positions. The vacuum cleaner has at least one motor and fan assembly for receiving power and producing airflow during use of the vacuum cleaner. The vacuum cleaner also has at least one sensor adapted to sense a change in the position of the vacuum cleaner and to alter the power provided to the at least one motor and fan assembly in response thereto.

Divisional application of U.S. patent application Ser. No. 09/576,249filed on May 24, 2000, now U.S. Pat. No. 6,457,205, Oct. 1, 2002.

FIELD OF THE INVENTION

This invention relates to a vacuum cleaner having a plurality of powermodes and more specifically to a power control system for such acleaner.

BACKGROUND OF THE INVENTION

Historically, power control systems for vacuum cleaners have beendesigned to provide a uniform flow of power. In the case of vacuumcleaners with electrical motors, power delivery systems have beendesigned so as to ensure a continuous flow of electricity to the motorso that the drive shaft driven by the motor runs at a constant rate ofrevolution.

More recently, developments have been directed towards providingvariable speed control for vacuum motors. U.S. Pat. No. 6,008,608, whichissued to Holstein et al., discloses a switch and speed control assemblyfor an electronically controlled vacuum cleaner motor. Holstein et al.'608 provides a control member coupled to a voltage varying device thatregulates the amount of power supplied to the vacuum cleaner motorcontrol circuit. The control member includes a thumb wheel which isoperated by the user to manually adjust the voltage varying device toselectively vary the speed of the vacuum cleaner motor. Holstein et al.'608 teaches that a spring may apply a counterforce to the controlmember to return the motor speed to a normal operating condition aftermomentarily engaging a “high on” mode. Thus, in Holstein et al. '608,the user must manually operate the control member.

In U.S. Pat. No. 4,969,229, which issued to Svanberg et al., a batteryoperated surface treatment apparatus having a booster function isdisclosed in which a separate battery is connected in series with thebatteries in the main power supply unit in order to temporarily boostthe power. A knob is manually operated to activate the booster function.A timing control is optionally provided to limit the period of operationof the booster function in order to prevent overheating. Svanberg et al.'229 indicates at column 1, lines 27-31, that the invention is directedto vacuum cleaners not provided with any electronic speed control.

In U.S. Pat. No. 4,811,450, which issued to Steadings, a vacuum cleanerhaving an auxiliary cleaning means is disclosed. The auxiliary cleaningmeans of Steadings '450 includes a flanged portion which is used todivert the suction force in a main suction air channel into an auxiliarycleaning hose. According to Steadings '450, during auxiliary cleaning,an increased suction force may be created in the auxiliary hose byclosing off the air flow in the main suction air channel, therebyrelieving part of the load on the common suction motor. Steadings '450explains that such relief results in increased rotational speed of themotor, which in turn correspondingly increases the suction air flow inthe auxiliary hose. However, Steadings '450 makes it clear, at column 1,lines 54-60, that in the auxiliary mode, the increase in the operationalspeed of the suction motor is obtained without requiring any electronicmotor control or regulation.

SUMMARY OF THE INVENTION

The present invention is directed to a vacuum cleaner having a pluralityof power modes, and to a power control system which is capable ofmaintaining the cleaning performance of the vacuum cleaner in thosevarious power modes and/or of controlling the power output to extend theoperational life of a battery operated vacuum cleaner. Briefly, thepower control system includes one or more sensors or switches which areused to sense the mode of operation of the vacuum cleaner. Signals fromthe one or more sensors or switches are then directed to amicroprocessor which in turn varies a power supply signal being providedto the vacuum cleaner motor.

In accordance with an aspect of the present invention, there is provideda vacuum cleaner having a plurality of operating modes, comprising:

(i) at least one motor and fan assembly for receiving a power supplysignal and producing a suction airflow during use of the vacuum cleaner;

(ii) at least one sensor for automatically sensing a change in theoperating mode of said vacuum cleaner and generating a mode signal inresponse thereto; and

(iii) a microprocessor responsive to said mode signal and adapted tovary said power supply signal.

In a preferred embodiment, the vacuum cleaner has a plurality ofdistinct operating positions and at least one sensor is adapted to sensea change in the operating mode based on a change in the operatingposition of said vacuum cleaner.

In another embodiment, the vacuum cleaner comprises a cleaning head anda main casing pivotally connected to said cleaning head, and at leastone sensor is adapted to sense when said main casing is positionedgenerally vertically above said cleaning head to sense that said vacuumcleaner is in standby operating mode.

In yet another embodiment, the vacuum cleaner comprises a cleaning head,a main casing pivotally connected to said cleaning head and an auxiliaryhose, and at least one sensor is adapted to sense when said main casingis positioned generally vertically above said cleaning head and saidvacuum cleaner is configured such that said auxiliary hose is in airflowcommunication with said motor and fan assembly and to generate a highflow mode signal in response thereto.

In another embodiment, the vacuum cleaner is an upright vacuum cleanerand further includes an auxiliary hose connectable in airflowcommunication with said motor and fan member assembly, and a high flowmode sensor for sensing when said auxiliary hose is in use.

More preferably, the vacuum cleaner includes a receptacle for releasablyreceiving said auxiliary cleaning hose, said high flow mode sensor beingprovided in said receptacle for sensing when said auxiliary cleaninghose is released from said receptacle.

In an alternative embodiment, the vacuum cleaner further comprises atleast one power supply for generating said power supply signal. Thepower supply may comprise a rechargeable battery.

In an embodiment including a rechargeable battery, the vacuum cleanerpreferably includes at least one sensor adapted to sense when saidvacuum cleaner is in battery recharge mode and to generate a rechargemode signal in response thereto, said microprocessor being responsive tosaid recharge mode signal and being adapted to vary said power supplysignal to operate said motor in a low flow mode, whereby airflow isproduced to cool said battery during recharge.

In another aspect of the present invention, there is provided a vacuumcleaner having a plurality of operating modes, comprising:

(i) suction means for receiving a power supply signal and producing asuction airflow during use of the vacuum cleaner;

(ii) sensor means for sensing a change in the operating mode of saidvacuum cleaner and generating a mode signal in response thereto; and

(iii) processor means responsive to said mode signal and adapted to varysaid power supply signal.

In a preferred embodiment, the vacuum cleaner has a plurality ofdistinct operating positions and the sensor means is adapted to sense achange in the operating mode based on a change in the operating positionof said vacuum cleaner.

In another embodiment, the sensor means includes a standby mode sensorfor sensing a standby mode and generating a standby mode signal inresponse thereto, said processor means being adapted to vary said powersupply signal in response to said standby mode signal so that saidsuction means is operated at decreased power as compared to normal modewhen said vacuum cleaner is used to clean a surface.

In yet another embodiment, the sensor means further includes a high flowmode sensor for sensing a high flow mode and generating a high flow modesignal in response thereto, said processor means being adapted to varysaid power supply signal so that said suction means is operated atincreased power as compared to the normal mode.

In an embodiment including a rechargeable battery, the vacuum cleanerpreferably includes a battery recharge mode sensor for sensing a batteryrecharge mode and generating a battery recharge mode signal in responsethereto, said processor means being adapted to vary said power supplysignal to operate said suction means in a low flow mode, so that airflowis produced to cool said battery during recharge.

In yet another aspect of the present invention, there is provided avacuum cleaner having a plurality of operating modes, comprising:

(i) at least one motor and fan assembly for receiving a power supplysignal and producing a suction airflow during; use of the vacuumcleaner, said vacuum cleaner having a plurality of distinct operatingpositions, each of said operating modes corresponding to one of saiddistinct positions;

(ii) at least one switch for generating a mode signal corresponding toat least one of the operating modes; and

(iii) a microprocessor responsive to said mode signal and adapted tovary said power supply signal.

In one embodiment, the vacuum cleaner includes a standby mode switch forgenerating a standby mode signal when said vacuum cleaner is in astandby mode position, said processor means being adapted to vary saidpower supply signal in response to said standby mode signal so that saidmotor and fan assembly is operated at decreased power as compared tonormal mode when said vacuum cleaner is used to clean a surface.

In another embodiment, the vacuum cleaner includes a high flow modeswitch for generating a high flow mode signal when said vacuum cleaneris in a high flow mode position, said processor means being adapted tovary said power supply signal in response to said high flow mode signalso that said motor and fan assembly is operated at increased power ascompared to normal mode when said vacuum cleaner is used to clean asurface.

In yet another embodiment, the vacuum cleaner includes a batteryrecharge mode switch for generating a battery recharge mode signal whensaid vacuum cleaner is in a battery recharge mode position, saidprocessor means being adapted to vary said power supply signal tooperate said motor and fan assembly in a low flow mode, so that airflowis produced to cool said battery during recharge.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other advantages of the instant invention will be more fullyand particularly understood in connection with the following descriptionof the preferred embodiments of the invention in which:

FIG. 1 is a schematic of a circuit which may be used in a power controlsystem for a vacuum cleaner according to an embodiment of the presentinvention;

FIG. 2 is a cross-section of a vacuum cleaner including the circuit ofFIG. 1, shown operating in normal mode;

FIG. 3 is a cross-section of the vacuum cleaner of FIG. 2 shownoperating in standby mode;

FIG. 4 is a cross-section of the vacuum cleaner of FIG. 2 operating inhigh flow mode with an auxiliary cleaning hose detached from the maincasing; and

FIG. 5 is a partial break away top plan view of the vacuum cleaning headof FIG. 2 including a battery and a separate cooling motor and fanassembly.

DESCRIPTION OF THE PREFERRED EMBODIMENT

The teachings of the present invention are directed to improving theperformance and efficiency of vacuum cleaners in general, and morespecifically to maintaining the efficiency of the vacuum cleaner invarious operating modes by means of a power control system.

By operating the vacuum cleaner in one of a plurality of possibleoperating modes, depending on the cleaning task, a degree of improvedperformance and efficiency will be achieved. As mentioned, possibleoperating modes may include a “normal” operating mode, a “high flow”mode for auxiliary cleaning, a “standby” mode for reduced speed duringinterruptions in vacuuming, and a “battery recharge” mode for batteryoperated vacuum cleaners.

Referring to FIG. 1, a motor control circuit is shown which may be usedin a vacuum cleaner in accordance with the instant invention. FIGS. 2, 3and 4 exemplify a vacuum cleaner which may include the circuit of FIG.1. It will be appreciated that the vacuum cleaner may be of anyconstruction known in the art. As shown in FIG. 2, a vacuum cleaner 70has vacuum cleaner head 72 and main casing 74. FIG. 2 shows the vacuumcleaner 70 operating in the normal floor cleaning mode referred toearlier (i.e. cleaning head 72 is being used to clean the surface overwhich cleaner head 72 travels). Cleaning head 72 has rear wheels 76 andfront wheels 78 to enable movement of cleaning head 72 across a surface.Cleaning head 72 is provided with a rotatably mounted brush 80 which ispositioned above air inlet 82. Cleaning head 72 has an air outlet 84positioned at the end of air flow path 86.

Main casing 74 contains the filtration means which preferably comprisescyclone housing 90 defining cyclone chamber 92. Cyclone chamber 92 isprovided with an air inlet 94 which is in air flow communication withair outlet 84 by means of air flow path 100.

Motor 98 is positioned above and downstream from air outlet 96. Outlet108 from vacuum cleaner 70 is provided downstream from motor 98.Additional filtration means may be provided, if desired, in one or bothof chambers 104 and 106. Handle 110 is provided so as to enable thevacuum cleaner to be pushed by a user.

Now referring to FIG. 3, the vacuum cleaner 70 of FIG. 2 is shown in thestandby mode referred to earlier. Rotatable valve 88 is provided in thecleaning head 72 so as to isolate the filtration means in main casing 74from air flow path 86 when the vacuum cleaner 70 is in the uprightposition (i.e. the main casing 74 is positioned generally verticallyover the cleaning head 72).

A first microswitch 140 senses when the vacuum cleaner 70 is in theupright position and sends a signal to a microcontroller 116 (FIG. 1) tovary the power signal to cause the motor to operate on standby, as willbe explained further below. It will be appreciated that air flow paths86 and 100 need not be isolated to utilize the standby mode.

Now referring to FIG. 4, as shown, vacuum cleaner 70 may also be adaptedfor above floor cleaning by means of an auxiliary cleaning hose 102which is releasably connectable to main casing 74 by any means known inthe art. A second microswitch 146 detects that the hose 102 has beenremoved from its receptacle and sends a signal to the microcontroller116 to cause the motor to operate in the high flow mode referred toearlier, and as described further below. In the embodiment of the vacuumcleaner 70 shown in FIG. 4, it is preferable that the vacuum cleaner 70first be put into the standby mode as shown in FIG. 3 so that all of theair travels through hose 102. Consequently, a vacuum cleaner 70 may gothrough an intermediate standby mode when switching between the normalmode and the high flow mode described above. However, it will beappreciated that this need not be the case in another vacuum cleanerconfiguration. In fact, it will be appreciated by those skilled in theart that the motor control circuit of the instant application may beutilized with virtually any vacuum cleaner, such as with a vacuumcleaner using any filtration means known in the art, as well as any typeof vacuum cleaner, e.g. upright, canister, back-pack and central vacuumsystems.

According to one aspect of the instant invention, the motor controlcircuit may be utilized with a vacuum cleaner which is to be pluggedinto a standard electrical outlet in a house. In such a case, the powercontrol system may be designed to provide full power in the high flowmode and to reduce the current provided to the motor in the normal mode.Alternately, the power control system may also be used with a vacuumcleaner which is powered by batteries and preferably rechargeablebatteries. In such a case, the power control system may be designed toprovide a standard level of power in the normal mode and to increase thepower drawn from the batteries during the high flow mode. Preferably, insuch a case, the power control system also controls the charging anddischarging the batteries.

Referring back to FIG. 1, power control circuit 112 comprises a motorcontroller as well as a battery charger. Battery 114 supplies 50% of thepower for motor 98 as DC current. The other half of the power issupplied to the motor through an inverter (namely field effecttransistor 120 and transformer 122). This has the advantage that halfthe power is transmitted as DC (which has nominal circuit losses) andhalf is transmitted through the inverter (which may have an efficiencyof eg. about 85%) for an overall efficiency of about 92.5%. It isrecognized that by increasing the power channelled through the inverter,the flow rate of the mechanical system can be controlled. However,increasing the power channelled through the inverter increases the heatlosses through the circuit and mitigates a portion of the energy savingrealized in the fluid mechanical portion of the system. It will beappreciated the battery 114 may supply all of the power to motor 98through the inverter circuit resulting in about a 7.5% reduction in thepower savings. The instant design also advantageously allows multiplepower levels to be supplied to motor 98.

Still referring to FIG. 1, the vacuum cleaner is operated by a userturning the vacuum cleaner on by an on/off switch 118, which may be anyswitch known in the art. When vacuum cleaner 70 is turned on,microcontroller 116 receives a signal from switch 118 and in turn startsto oscillate field effect transistor 120 at a high frequency (e.g. about60 KHz). Circuit 112 is provided with transformer 122 having primary andsecondary coils 124 and 126. The high frequency oscillation produced byfield effect transistor 120 causes primary coils 124 to induce a highvoltage in secondary coils 126. The high voltage induced in second coil126 is switched on and off by field effect transistor 128 at a muchlower frequency (e.g. 9 Hz) as controlled by microcontroller 116 bymeans of wire 152 to create a pulse train signal. The high voltageinduced in second coil 126 may also be supplied to diode multiplier 172to provide current to, eg. an electrostatic generator in vacuum cleaner70.

Field effect transistor 128 is connected to motor 98 via wire 130,switch 132 and wire 134. Accordingly, the pulse train developed by fieldeffect transistor 128 is supplied to motor 98 so as to causesub-rotational accelerations as described herein whereby the efficiencyof the power transfer from motor 98 to the fluid stream passing throughvacuum cleaner 70 is improved.

In a cyclonic vacuum cleaner, the impulses are preferably 1/81 secondslong having a voltage (amplitude) six times greater than the DC voltagesupplied by battery 114 to motor 98 by means of wires 136, 138. Thefrequency of the pulses produced by field effect transition 128 ispreferably 6-20 Hz for a cyclonic vacuum cleaner using a seriesuniversal motor wound to produce the desired flow rate when 50 volts ACis applied with 200 watts available. It will be appreciated that thepulse which is provided to motor 98 may be varied by changing thefrequency of field effect transistor 128.

Still referring to FIG. 1, in accordance with another aspect of thisinvention, circuit 112 may include a first microswitch 140 which isactivated when vacuum cleaner 70 is placed in the upright standbyposition shown in FIG. 3. Microswitch 140 may be of any known in the artwhich will provide a signal to microcontroller 116 when upper casing 74is in the upright position shown in FIG. 3. In the embodiment shown inFIG. 3, the upright position is sensed due to engagement between uppercasing 74 and microswitch 140. Alternatively, the sensor may be mountedon upper casing 74 to engage the vacuum cleaner head 72 and sense whenupper casing 74 is in the upright position or the sensor may sense whenupper casing 74 extends generally vertically. It will be understood thatthe sensor may be provided at any other location where it can sense theupright position (e.g. the sensor may be provided at the pivot pointbetween the vacuum cleaner head 72 and the upper casing 74).

As explained earlier, first microswitch 140 causes a signal to be sentto microcontroller 116 by means of wire 142. This causes microcontroller116 to terminate the oscillation of field effect transistors 120 and 128thereby reducing the power consumption and air flow through motor andfan blade assembly 98.

Typically, a user may leave a vacuum cleaner running when in the uprightposition when attending to other tasks associated with vacuuming such asto move furniture or other objects which may be in the way. When firstmicroswitch 140 is actuated, moving the vacuum cleaner into a standbymode, the power consumed by motor and fan blade assembly 98 is reducedthereby permitting a user to move furniture, answer the telephone or thelike while reducing the power consumption of motor and fan bladeassembly 98. Microswitch 140 may be utilized to switch a vacuum cleaneroperating from a standard electrical outlet to a standby mode. This maybe advantageous to decrease the noise produced by vacuum cleaner 70 whenit is not being used. However, use of the standby mode is particularlyadvantageous in a battery powered vacuum cleaner in order to conservethe battery.

Now referring to FIG. 4, optionally, hose 102 is detachable from maincasing 74, e.g., in the direction of arrow B so as to enable above thefloor cleaning. Hose 102 may have a crevice cleaning tool or otherattachment 144 slidably received therein in the direction of arrow C. Insuch a case, circuit 112 preferably also includes a second microswitch146 for switching motor and fan blade assembly 98 to a high flow mode.The higher flow is desirable for enhanced cleaning using the accessorytools 144. Alternately, as the use of a length of hose causes additionalpressure losses, increasing the power provided to motor and fan bladeassembly 98 may result in the same flow rate through the filtrationmeans when hose 102 is used. Microswitch 146 may be provided in thereceptacle in which hose 102 is received and actuated when hose 102 isreleased from the receptacle (in the direction of arrow B). Microswitch146 may be a pressure actuated switch (i.e. the switch may have a buttonwhich is pressed inwardly) or may be a proximity switch which senses thepresence of hose 102 in its receptacle. When hose 102 is released, thebutton extends outwardly thereby sending a signal to microcontroller 116by means of wire 148. In response to this signal, microcontroller 116sends a signal to field effect transistors 120 and 128 by means of wires150 and 152 respectively. This causes field effect transistor 120 tooscillate at a high frequency (e.g. 60 KHz or greater) and cause fieldeffect transistor 128 to oscillate at a higher frequency than before(e.g. 11-15 Hz) with pulses of, e.g. 1/81 to 1/60 of a second for atypical cyclonic vacuum cleaner as described above. The longer pulsewidth and/or greater frequency of pulses delivered to motor and fanblade assembly 98 produces a higher flow of air through vacuum cleaner70 then when the vacuum cleaner is drawing dirt laden air through inlet82.

Microcontroller 116 also preferably includes a circuit for determining alevel of charge remaining in battery 114. To this end, microcontroller116 sends a signal to field effect transistor 120 which causes fieldeffect transistor to switch on for a short period (e.g. approximately0.1-0.2 seconds). This produces an impulse equivalent to DC. As thefrequency of this impulse is very low, transformer 122 effectivelybecomes a low resistance short circuit across battery 114 therebycausing a current surge through low value resistor 154 which is serieswith transformer 122.

The voltage drop across low value resistor 154 caused by the currentsurge is conducted to (e.g.) the analog to digital port ofmicrocontroller 116 by means of wires 156 and 158. While the voltagewhich is supplied by battery 114 may be relatively constant over asubstantial portion of the operating life of a battery (e.g. 75% ormore), it has surprisingly been determined that the rate of rise ofcurrent in response to a momentary short circuit does not remainconstant. In particular, as the capacity of the battery is reduced (i.e.charge is withdrawn from the battery), the ability of battery 114 tosupply a current surge is also reduced. Therefore, it is possible todetermine the capacity remaining in the battery by occasionallyproducing a short circuit across battery 114 and monitoring the rate ofrise of the current in response to the short circuit. For a NiMH sub Cbattery pack comprising two sets of twelve sintered cells connected inparallel, the di/dt varies from 300 A/S to 120 A/S from 90% capacity to20% capacity while the voltage output is essentially constant. Thus, byknowing the di/dt relationship for a battery over the capacity for abattery, microcontroller 116 may provide a signal indicating the amountof capacity remaining in the battery or, if the battery is beingcharged, the degree to which the battery has been charged.

The same method may be utilized during the recharging of the battery todetermine the charge state of the battery. Typically, the charge stateof the battery is determined using the −ΔV. When a battery is in the −ΔVrange, it is already overcharged. Rechargeable batteries are subject todegradation if their temperature increases too much, which occurs whenthey are overcharged. Therefore, it is advantageous to determine thecharged state of a battery prior to the battery becoming overcharged.Accordingly, during the recharging of a battery, microcontroller 116 maycause field effect transformer 120 to occasionally emit a low frequencypulse thereby producing a current surge which may be measured by thevoltage drop across low value resistor 154.

Preferably, microcontroller 116 includes means for opening the circuitto thereby shut off motor and fan blade assembly 98 when battery 114 isat a sufficiently low charge level. Accordingly, circuit 112 may shutdown the power drawn from battery 114 by opening relay 160 which opensthe circuit to motor and fan blade assembly 98 and by terminating thesignals which are send to field effect transistors 120 and 128.

It will be appreciated that battery 114 may be charged by removingbattery 114 from vacuum cleaner 70 and placing it in a suitable chargingunit. Preferably, battery 114 is charged in situ. To this end, vacuumcleaner 70 may include a plug 162 which is suitable for being receivedin a standard electrical outlet. Plug 162 is connected to circuit 112 bymeans of cord 164. When plug 162 is withdrawn from receptacle 166 (whichmay be provided at any desired position in vacuum cleaner 70),mechanical lever 168 trips switch 132 so as to disconnect motor and fanblade assembly 98 from the current. In this way, motor and fan bladeassembly 98 (FIG. 2) will still receive current from wires 136 and 138thereby causing motor and fan blade assembly 98 to operate at low powerduring the recharging operation.

When plug 162 is removed from receptacle 166, a signal is sent tomicrocontroller 116 such that when plug 162 is plugged into a standardpower outlet, field effect transistor 128 is operated at, e.g. 60 KHz bymicrocontroller 116 while field effect transistor 120 provides lowfrequency pulses (eg. 10 Hz) to charge battery 114. The frequency ofoperation of field effect transistor 128 can be raised or lowered tovary the output voltage used to charge battery 114.

As will be appreciated, the operation of the motor and fan bladeassembly 98 at low voltage DC during the recharging operation causesmotor and fan blade assembly 98 to operate at a low speed so that airmay be drawn across battery 114 and over, e.g., heat sink 170 which isthermally connected to battery 114 so as to cool battery 114 while it isbeing charged.

Optionally, a switch 132 may be arranged to disconnect wire 136 frommotor and fan blade assembly 98 so that motor and fan blade assembly 98will not operate during the charging mode. Rather, referring to FIG. 5,a separate cooling motor and fan assembly 99 may be provided in air flowcommunication near battery 114 to reduce the sensible temperature ofbattery 114 during charging.

As stated above, possible operating modes may include a “normal”operating mode, a “high flow” mode for auxiliary cleaning, a “standby”mode for reduced speed during interruptions in vacuuming, and a “batteryrecharge” mode. A vacuum cleaner according to the present invention mayutilize any two of these operational modes in which case one switch isincluded for sending a signal to change between the modes. Preferably,the vacuum cleaner may be switched between any three of these modes (inwhich case the vacuum cleaner includes two switches) and, mostpreferably, the vacuum cleaner may be switched between all four modes(in which case it has three switches). It will be appreciated that therecharge mode is only applicable on battery operated vacuum cleaners.

The vacuum cleaner may use any switch or switches known in the art (e.g.mechanical or electrical; manual or automatic) and different operatingmodes may be actuated by different switches. Preferably the switches areconstructed to automatically switch the current provided a motor when auser reconfigures the vacuum cleaner between, e.g., carpet cleaning andabove the floor cleaning, when the vacuum cleaner is placed in thestandby position or when a battery operated vacuum cleaner is recharged.However, switches which are manually operated by the user may be used toactivate the various operating modes when the user reconfigures thevacuum cleaner.

It will be appreciated that the circuit of FIG. 1 is exemplary and thatany power control circuit may be used to adjust the current provided tothe motor.

I claim:
 1. A vacuum cleaner reconfigurable between at least twopositions, the vacuum cleaner comprising: (a) at least one motor and fanassembly for receiving power and producing an airflow during use of thevacuum cleaner; and, (b) at least one sensor adapted to sense a changein the position of the vacuum cleaner and to alter the power provided tothe at least one motor and fan assembly in response thereto.
 2. Thevacuum cleaner as claimed in claim 1 wherein the vacuum cleanercomprises a cleaning head and a main casing pivotally connected to thecleaning head, the at least one sensor being adapted to sense when themain casing is positioned generally vertically above the cleaning head.3. The vacuum cleaner as claimed in claim 1 wherein the vacuum cleanercomprises a cleaning head, a main casing pivotally connected to thecleaning head and an auxiliary hose, the at least one sensor beingadapted to sense when the main casing is positioned generally verticallyabove the cleaning head and the vacuum cleaner is configured such thatthe auxiliary hose is in airflow communication with the motor and fanassembly, whereby the power provided to the at least one motor and fanassembly is increased.
 4. The vacuum cleaner as claimed in claim 1wherein the vacuum cleaner is an upright vacuum cleaner, the uprightvacuum cleaner further includes an auxiliary hose connectable in airflowcommunication with the motor and fan member assembly, and a high flowmode sensor for sensing when the auxiliary hose is in use.
 5. The vacuumcleaner as claimed in claim 4 further including a receptacle forreleasably receiving the auxiliary cleaning hose, the high flow modesensor being provided proximate the receptacle for sensing when theauxiliary cleaning hose is released from the receptacle.
 6. The vacuumcleaner as claimed in claim 1 further comprising at least one powersupply for generating the power.
 7. The vacuum cleaner as claimed inclaim 6 wherein the at least one power supply comprises a rechargeablebattery.
 8. The vacuum cleaner as claimed in claim 7 wherein the atleast one sensor is adapted to sense when the vacuum cleaner is inbattery recharge mode and to generate a recharge mode signal in responsethereto.
 9. The vacuum cleaner as claimed in claim 7 further comprisingan auxiliary motor and fan assembly, the auxiliary motor and fanassembly being located proximate to the battery and being connectable toa power source, the at least one sensor being adapted to sense when thevacuum cleaner is in battery recharge mode and being adapted to turn onthe auxiliary motor and fan assembly so as to cool the battery duringrecharge.
 10. A vacuum cleaner reconfigurable between at least twopositions, the vacuum cleaner comprising: (a) suction means forreceiving power and producing a suction airflow during use of the vacuumcleaner; and, (b) sensor means for sensing a change in the position ofthe vacuum cleaner and altering the power provided to the suction meansin response thereto.
 11. The vacuum cleaner as claimed in claim 10wherein the sensor means includes a standby mode sensor for sensing astandby mode wherein a reduced power level is provided to the suctionmeans in response thereto.
 12. The vacuum cleaner as claimed in claim 11wherein the sensor means further includes a high flow mode sensor forsensing a high flow mode wherein an increased power level is provided tothe suction means in response thereto.
 13. The vacuum cleaner as claimedin claim 12 further comprising a rechargeable battery wherein the sensormeans further includes a battery recharge mode sensor for sensing abattery recharge mode wherein a reduced power level is provided to thesuction means in response thereto so that airflow is produced to coolthe battery during recharge.
 14. The vacuum cleaner as claimed in claim11 further comprising a rechargeable battery wherein the sensor meansfurther includes a battery recharge mode sensor for sensing a batteryrecharge mode wherein a reduced power level is provided to the suctionmeans in response thereto so that airflow is produced to cool thebattery during recharge.
 15. The vacuum cleaner as claimed in claim 10wherein the sensor means includes a high flow mode sensor for sensing ahigh flow mode wherein an increased power level is provided to thesuction means in response thereto.
 16. The vacuum cleaner as claimed inclaim 10 further comprising a rechargeable battery wherein the sensormeans includes a battery recharge mode sensor for sensing a batteryrecharge mode wherein a reduced power level is provided to the suctionmeans in response thereto so that airflow is produced to cool thebattery during recharge.
 17. The vacuum cleaner as claimed in claim 10wherein the vacuum cleaner is an upright vacuum cleaner having acleaning head and an upper casing mounted thereon, the vacuum cleaneroperating in a normal mode when the cleaning head is used to clean asurface, and the sensor means includes a high flow mode sensor forsensing a high flow mode when an auxiliary hose is in use and causingthe suction means to produce an increased air flow through the vacuumcleaner.